Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher CZ-21 Metal Detector with an 8-inch waterproof searchcoil, submersible up to 250 feet, dual-frequency operation, target ID, and adjustable ground balance, ideal for underwater and beach treasure hunting.
Fisher: Since 1931

Fisher CZ21 Underwater Multi-Frequency Metal Detector

$1,799.00 USD
Free US Shipping
{price}% OFF
Find a Dealer
Untitled_design_3_7af8c1c5-e612-43a9-9d74-845ed6bbc60f.png

Customer Reviews

Be the first to write a review
0%
(0)
0%
(0)
0%
(0)
0%
(0)
0%
(0)

Committed to Gear That Goes the Distance

  • Free Shipping

    Available on US orders over $50

  • Up to 2-Year Warranty

    Coverage you can count on

  • 30-Day Returns

    Shop with confidence

  • Dedicated Support

    Get expert help from real people

Product Description

The Fisher CZ-21 is a professional-grade metal detector designed for serious treasure hunters who explore land, beaches, and underwater environments. Built to withstand depths of up to 250 feet, it’s perfect for divers, beachcombers, and anyone searching in wet or mineralized conditions. What sets it apart is its dual-frequency VLF technology, providing advanced target analysis in both salt and freshwater.


The CZ-21 uses simultaneous 5 kHz and 15 kHz frequencies to deliver deep, accurate target detection across a range of soil and water conditions. Its 3-tone audio Target-ID system helps you distinguish between iron, foil, and coins or jewelry without even looking at the control panel. The unit features a silent-search discrimination mode, Auto-Tune for all-metal searching, and a V.C.O. pinpoint mode for precision target recovery. With features like manual ground balance, audio boost for faint targets, and saltwater compensation, it adapts to even the toughest environments.


Designed for extreme conditions, the CZ-21 is housed in a waterproof shell and includes permanently attached waterproof headphones. Its durable fiberglass construction, hip-mountable control box, and adjustable armrest make long hunts comfortable and manageable. Powered by four 9V batteries, it offers up to 55 hours of operation, ensuring you stay in the field longer without interruptions. Whether on the beach or beneath the waves, the CZ-21 is engineered for performance and built to last.


Purpose: Deep Diving, Relic Hunting, Coin Shooting, Beach Hunting, Jewelry

Specifications

  • Manufacturer: First Texas Products, LLC
  • Brand Name: Fisher Research Labs
  • Country of Origin: USA
  • Warranty: 2 Years
  • Technology: VLF
  • Frequency: Dual Frequency - 5 kHz & 15 kHz
  • Operating Modes: 3 (Target-ID | Auto-Tune | Pinpoint)
  • Ground Balance: Manual
  • Discrimination: Yes
  • Target ID: No
  • Numeric ID: No
  • Fe Readout: No
  • Fe-Tone Audio: No
  • Audio: Yes, 3-Tone Audio Feedback (|Low | Medium | High)
  • Volume: Yes, 10-Level Adjustment
  • Sensitivity: Yes, 10-Level Adjustment
  • Depth Indicator: No
  • Pinpoint: Yes
  • Memory: No
  • Backlight: No
  • Display: Analog
  • Weatherproof: Yes (fully submersible to 250 ft)
  • IP Rating: IP54
  • Stock Searchcoil(s): 8" or 10"
  • Headphone Jack: No (Includes permanently attached waterproof headphones)
  • Weight: 5 lbs. 11 oz. (2.6 kg)
  • Battery Type: 4 x 9V (Not Included)
  • Battery Life: 35-5 Hours (Alkaline Recommended)

    • Shop

    Parts & Accessories

    Manual

    CZ21

    Support

    For more information and to purchase, visit where to buy , email us , chat with us, or call us at 1-800-685-5050   for any questions.
    For repair service in warranty or out of warranty please fill out the RMA form.

    Videos

    Coming soon

    Frequently Asked Questions

    What is the advantage of the CZ-21’s dual-frequency operation (5 kHz & 15 kHz)?

    The dual VLF frequencies allow the CZ-21 to analyze targets with better depth and conductivity discrimination. The 5 kHz penetrates deeper for high-conductivity items like silver, while 15 kHz is more sensitive to smaller, low-conductivity targets like gold. Combined, they provide more accurate target ID, especially in mineralized or saltwater environments.

    Can I ground balance separately in Auto-Tune and Target-ID modes?

    Ground balancing in one mode (Auto-Tune or Target-ID) automatically applies to both. Once set, you can switch between modes without rebalancing — unless ground conditions change significantly.

    How does saltwater compensation work on the CZ-21?

    The CZ-21 uses Fourier domain signal analysis to filter out the conductivity effects of saltwater, which normally causes false signals in many VLF detectors. This allows stable operation even in wet sand and surf zones without needing Pulse Induction technology.

    Why does my detector give a ‘bell tone’ instead of the standard audio response?

    The bell tone is a big-target alert. It indicates circuit overload, usually from large, shallow objects. This feature protects the unit from misidentifying high-signal targets and alerts you to investigate or move on.

    How precise is the V.C.O. pinpoint mode, and how does it function?

    The Voltage-Controlled Oscillator (V.C.O.) pinpoint feature provides a variable tone that increases in pitch and volume as you center over a target. It allows no-motion pinpointing with greater precision than motion-only search modes.

    What causes the CZ-21 to produce false signals at the end of a sweep?

    This is typical of motion-based detectors. As the coil decelerates and reverses direction, uneven motion can trigger end-of-swing chatter. To reduce this, maintain a smooth, even sweep and lower sensitivity if needed.

    Can I hip-mount the control housing for land use, and does it affect performance?

    Yes, the control box can be hip-mounted to reduce arm fatigue. However, if not enough slack is left in the cable, the coil may detect the housing during sweeps, causing false signals. Always secure the cable to prevent detection of the housing.

    What is the optimal sensitivity setting for diving in saltwater?

    Start at a sensitivity of “3” as marked on the control panel for saltwater operation. This reduces salt chatter. Gradually increase only if conditions allow stable performance. Always re-ground balance after adjustments.

    How does the CZ-21 differentiate between a gold ring and foil or pull tabs?

    Most gold rings fall within the same conductivity range as foil and pull tabs, giving a mid-tone. However, the CZ-21’s discrimination settings allow experienced users to test responses and isolate likely gold targets using audio cues and quick rechecking techniques.

    Can the CZ-21 use interchangeable coils or headphones?

    No. The searchcoil and headphones are permanently attached and not interchangeable. This ensures watertight integrity for full submersion up to 250 feet. Any service must be performed by the factory to preserve the seal.

    Testimonials

    What Our Customers Are Saying

    '...he found his first coin. A 1946 wheat. I'm glad to say we have a new Digger in the family."





    Untitled_design_1

    Landon Howlett

    Fisher F70

    This is a Union Officers belt plate from the Civil War, it was found at a G.A.R. 1895 Civil War reunion encampment...





    JimDoan

    Jim Doan

    Bounty Hunter Quickdraw II

    '...great detector please keep me informed on the new machines coming out i got pictures of your detectors for years finding things in fields that have been hunted by everything till the First Texas hit the ground.'


    RyanVecchio1

    Ryan Vecchio

    Bounty Hunter Platinum

    "Great contact information, wonderful interaction and the product is wonderful. I will expand my accessories, new usable work products, thanks for this convince and an all USA (EL Paso TX) buy local products."
    JamesKSample

    James K. Sample

    Fisher TW6

    '...i pulled the trigger on it just in time to detect the new yard my son was on and all i can say is this machine is one serious coin shooter the first yard I scan with it I get my first silver quarter (1946) and my first Morgan dollar (1900) which was 11in .

    DaveBrumfield

    David Brumfield

    Bounty Hunter QuickDraw Pro

    Shop by Brands

    BountyHunterLogoJPG960x66820250401
    FisherSportLogoJPG960x66820250401
    FisherUtilityLogoJPG960x66820250401
    FisherSecurityLogoJPG960x66820250401_f621f0dd-0d7a-489e-bd02-7f3f1f862f4d
    TekneticsLogoJPG960x66820250401_bca2d1f9-a16b-42ec-b4e8-2e56af59f91a
    NightOwlOpticsLogoJPG960x66820250401
    NivisysLogoJPG960x66820250401